<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    
</head>
<body>
    <form action="" method="get" id="form">
        <input type="radio" value="1" name="a" id="">aa
        <input type="radio" value="2" name="a" id="">bb
        <input type="submit" onClick="click">
        <div onclick="Myclick()">fafdasf</div>
    </form>
    <script>
        function Myclick(){
            var form = document.getElementById("form")
            console.log(form.elements[0].form)
            if(!form['a'].value){
                
            }else{
                
            }
            // e.preventDefault();
        }
    </script>
    
</body>
</html>